Connector cover

ABSTRACT

A protective and strain relief cover of sheet material construction is provided for a printed circuit board connector block having a multiplicity of conductor wires extending therefrom. The cover is U-shaped in cross section and includes a pair of legs and a bridging portion adapted to recieve the conductor wires therebetween. The legs of the cover are retained against lateral spreading by interengaging tab assemblies at opposite ends of the cover and which tabs also serve to interconnect the cover with the connector block. The legs of the cover are apertured to receive a tying strap by which the conductor wires are clasped in place with respect to the cover.

United States Patent 1 1 11 1 3,874,765

Gilmore et al. 1 1 Apr. 1, 1975 1 1 CONNECTOR COVER 3.732.526 5/1973Punako 339/103 R x 3,794,960 2/1974 Sugar 4 1. 339/107 [75] Inventors:Earl A. Gilmore, S1lv1s. 111.; Kenneth 3 803 530 4 1974 L 339/10; R x

E. Merklen, Cos Cob. Conn. I apml u T OR APPLICA N 173] Ass1gnee: Gulf &Western Industries, Inc., FOREIGN PATEN S no S New York NY 1.074.108H1960 Germany 339/164 R Filed: out 171 1973 Primary Iimminer-Roy D.Frazier 2 l] App| 407 Assistant Exmniner-Lawrence J. Staab Attorney,Agem, 0r FirmMeyer, Tilberry & Body [52] U.S. 339/103 M, 24/16PB.113/116 P 151 Int. Cl l-lOlr 13/58 [57] ABSTRACT [58] Field of Search24/16 PB; 29/183, 190: A protective and strain relief cover of sheetmaterial 113/116 PV, 119; 339/103-107, 136-140, 36 construction isprovided for a printed circuit board connector block having amultiplicity of conductor [56] References Cited wires extendingtherefrom. The cover is U-shaped in UNITED STATES PATENTS cross sectionand includes a pair of legs and a bridging 1 Us I mg Lunman 9H0, R Xportion adapted to recieve the conductor wires there 15311151 11/1929WM-.j;.';;"""';jjjijjjj;.i.i-... 211/190 tttwttthe tht tttttttttttttttttt 211111.531 6/1935 Galuntc 29/190 x lateral spre'ttdmg bylmerengagmg tab assembhes 1199319 4 194 Edwards c t 339 X opposite endsof the cover and which tabs also serve 2.318.230 5/1943 Jones 339/136 Mto interconnect the cover with the connector block. 2.474.908 7/1949Morin 29/1911 X The legs of the cover are apertured to receive a tying3. 5 3 10/1 Ctlrbflugh BI 339/103 M X strap by which the conductor wiresare clasped in 3.152119 10/1964 Murray et 21]. 339/105 UX place i hrespect to h cover 3.277.426 10/1966 KlostcrmunnH... 339/136 M X3.676.837 7/1972 Newman 339/103 R 20 Claims, 9 Drawing Figures CONNECTORCOVER The present invention relates to the art of electrical couplingsand, more particularly, to a cover for a multiple conductor connectorblock.

In the printed circuit board industry, connector blocks of insulatingmaterial are well known coupling components which provide fordisengageably connecting a plurality of electrical conductor wires toprinted conductors on a circuit board. In this respect, the printedconductors terminate at an edge of the board and the connector block hasan opening adapted to receive the edge of the board. Further, theconnector block carries a plurality of contacts which are mountedtherein for engagement with the printed conductors when the connectorblock and circuit board are assembled. A corresponding number of wiresare electrically interconnected with the contacts and extend from theblock.

The electrical conductors extending from the connector block areflexible and are bendable individually and as a unit relative to theconnector block. Accordingly, during assembly or disassembly of theconnector block with the circuit board, as well as during use of theassembly, the conductors are subject to bending and flexing relative tothe connector block which often leads to separation of one or more ofthe conductors from its contact within the block, or damage to theelectrical connection therebetween. It will be appreciated, therefore,that it becomes highly desirable to protect the conductor wires againstflexing relative to and- /or separation from a connector block duringand following assembly of the block with a circuit board and duringdisassembly thereof from the circuit board.

In accordance with the present invention, the desired protection of theconductor wires extending from a connector block of the foregoingcharacter is achieved by a cover structure readily interconnectable withthe conductor block. The cover is generally U-shaped in cross sectionand when assembled with a connector block the conductor wires aredisposed in the space between the legs and bridging portion of the U andare clasped in place with respect to the cover by a tying strapcomponent separate from or attached at one end to the cover. In additionto the protective function, the cover is economical to produce andoperatively associate with a connector block and conductor wires,whereby production and installation costs are minimized. Moreparticularly, the cover preferably is produced from thin sheet metal orplastic by first stamping or otherwise cutting a blank from the materialand then relatively bending and interengaging portions of the blank toprovide the U-shaped cover structure. The cover is then ready forassembly with respect to a connector block and the conductor wiresextending therefrom. The legs of the U are provided with opposedopenings for the tying strap which, if separate from the cover, isinserted through the openings to underlie the conductor wires. The freeends of the strap are then interengaged such as by twisting to clasp theconductor wires against the bridging portion of the U. In a modificationof the strap feature, one end of the strap is fastened to the coveradjacent one of the strap openings in the legs of the U. The free end ofthe strap is then inserted through the two openings to underlie theconductor wires, and the free end of the strap and the second openingare structurally interengageable to clasp the conductor wires in place.

It is an outstanding object of the present invention to provide aprotective cover for a multiple conductor connector block which is ofsimple construction and is readily assembled and disassembled withrespect to a connector block.

Another object is the provision of a cover of the foregoing characterwhich is economically and econimically produced and is comprised of aminimum number of parts.

Still another object is the provision of a cover of the foregoingcharacter which is formed from a blank of sheet material and which isretained in its formed shape for interconnection with a connector blockby interengaging components integral with the blank.

A further object is the provision of a cover of the foregoing characterin which the conductor wires of a connector block are releaseablyclasped to the cover by a flexible tying strap carried by or separatefrom the cover.

Still another object is the provision of a cover of the foregoingcharacter in which the tying strap is carried by the cover and iscooperable therewith to clasp the conductor wires in place.

The foregoing objects, and others, will in part be obvious and in partpointed out more fully hereinafter in conjunction with the writtendescription of preferred embodiments of the invention appearing in theaccompanying drawings in which:

FIG. I is a perspective view of a blank from which a cover made inaccordance with the present invention is formed;

FIG. 2 is a perspective view of a cover erected from the blank of FIG. 1and shown in assembled relationship with respect to a connector block;

FIG. 3 is a side elevational view of the cover illustrated in FIG. 2;

FIG. 4 is an end view, partially in section, of the cover and connectorblock assembly illustrated in FIG. 3, the section being along line 4-4in FIG. 3;

FIG. 5 is a perspective view of another embodiment of a cover made inaccordance with the present invention, showing the cover in assembledrelationship with a connector block;

FIG. 6 is an end elevation view, partially in section, of the cover andconnector block assembly illustrated in FIG. 5, the section being alongline 6-6 in FIG. 5;

FIG. 7 is an end elevation view of the cover illustrated in FIG. 5showing the cover prior to assembly with a connector block;

FIG. 8 is a side elevation view of a portion of the cover illustrated inFIG. 7, the view being along line 8-8 in FIG. 7; and,

FIG. 9 is a side elevation view of a portion of the cover illustrated inFIG. 7, the view being along line 99 in FIG. 7.

Referring now in greater detail to the drawings wherein showings are forthe purpose of illustrating preferred embodiments of the presentinvention only and not for the purpose of limiting the invention, aconnector block cover made in accordance with the present invention isadvantageously formed from a onepiece blank of sheet material such asblank 10 illustrated in FIG 1. Any suitable material, such as plastic,light gauge sheet metal or resin impregnated fiberboard can be employed.In the embodiment illustrated in FIG. 1, the blank is produced from asheet of light gauge aluminum and is cut to provide opposed side edges12 and I4 exending generally parallel to an imaginary axis A midwaytherebetween, and opposed end edges 16 and 18 extending generallyparallel to one another and perpendicular to axis A. Imaginary lines 20and 22 extend parallel to axis A and on opposite sides thereof anddivide the blank into side portions 24 and 26 and intermediate portion28 for the purpose set forth more fully hereinafter.

One end of blank has a pair of tabs 30 and 32 disposed on opposite sidesof axis A and extending longitudinally from end edge 16 approximatelythe same distance. Tabs 34 and 36 extend laterally inwardly from tab 32towards tab 30 and are integral with one another and with tab 32 alongfold lines 38 and 40. The opposite end of the blank is provided withsimilar tabs located at diagonally opposite corner areas of the blankfrom the corresponding tabs extending from edge 16. In this respect, tab42 similar to tab 30 extends longitudinally from end edge 18 of theblank and from the corner of the blank diagonally opposite that fromwhich tab 30 extends. Similarly, a tab 44 similar to tab 32 extendslongitudinally from end edge 18, and tabs 46 and 48 extend laterallyfrom tab 44 towards tab 42 and are integral with one another and withtab 44 along fold lines 50 and 52. Tab portions 34 and 46 are providedwith openings 54 and 56, respectively, for the purpose set forthhereinafter. Further, the blank is provided with a pair of openings 58and 60 adjacent end edge 16 and on opposite sides of axis A for thepurpose set forth hereinafter.

The cover structure illustrated in FIGS. 2, 3 and 4 of the drawing isadapted to be formed by erecting blank 10. In this respect, the blank isbent or curved relative to axis A to provide a U-shaped wall structurein which portions 24 and 26 of the blank define the legs of the U andintermediate portion 28 defines the bridging portion of the U. Tabs 34and 36 are then bent relative to tab 32 so that tab 34 extends inwardlyof the U and is generally perpendicular to tab 32 and tab 36 isgenerally parallel to tabs 32 and 30 and is disposed in facial overlyingengagement with the outer surface of tab 30. Similarly, tabs 46 and 48are bent relative to tab 44 so that tab 46 extends inwardly of the U andis generally perpendicular to tab 44 and tab 46 is generally parallel totabs 44 and 42 and facially overlies the latter tab. The tab structuresat opposite ends of the cover interengage leg portions 24 and 26 torestrain lateral separation thereof and, as pointed out hereinafter,further serve to support the cover relative to a connector block and tofacilitate the interconnection therebetween. It will be appreciated, ofcourse, that the described sequence of folding the various portions ofthe blank can be varied to achieve the erected structure.

When the cover is erected in the foregoing manner, it is adapted to beassembled with respect to a connector block having conductor wires to beprotected thereby. It will be appreciated that the connector block maybe defined by a variety of structural configurations. the structureillustrated being illustrative of one such structure with which thecover of the present invention can be employed. More particularly, withreference to FIGS. 2, 3 and 4 of the drawing, a connector block 62 isillustrated as being generally rectangular in cross-sectional contourhaving an outer or top surface 64, opposite sides 66 and 68 and mountinglugs 70 ex tending from opposite ends thereof, only one of which lugs isvisible in the drawings. A plurality of conductor wires 72 extendupwardly from top surface 64 and have inner ends disposed within theblock and electrically interconnected in a well known manner withcontact terminals not illustrated. Further, in a manner well known, thebottom of the block is slotted to receive the edge of a printed circuitboard B having printed conductors C on at least one surface thereof forengaging the contacts within the connector block.

When assembled with the connector block shown, legs 24 and 26 of thecover overlie sides 66 and 68 of the connector block, respectively, andbridging portion 28 is spaced above outer surface 64 of the connectorblock. Conductors 72 extend upwardly from outer surface 64 of theconnector block into the space thus defined and thence outwardly fromone of the open ends of the cover. Tabs 34 and 46 at opposite ends ofthe cover overlie mounting lugs of the connector block to position thecover vertically with respect thereto, and apertures 54 and 56 in tabs34 and 46 are adapted in the embodiment disclosed to receive the shanksof threaded fasteners 74 by which the cover is releasably interengagedwith the connector block. In the embodiment illustrated, fasteners 74are freely rotatable relative to mounting lugs 70, and suitableretaining elements 76 interengage the shanks of the fasteners to retainthe cover in place with respect to the connector block while permittingrotation of the fasteners 74. It will be appreciated, however, thatmounting lugs 70 of the block can be provided with openings threaded forengagement with fasteners 74 to achieve the desired interconnection, orthat nuts or the like can be threaded onto fasteners 74 to achieve thedesired interconnection. While the cover is preferably interconnectedwith the connector block through tabs 34 and 46, it will be appreciatedthat the interconnection between the connector block and cover can beotherwise achieved. In this respect, for example, fasteners such asscrews or threaded studs could extend through the leg portions of thecover and into threaded engagement with the connector block.

In addition to covering and protecting the conductors during engagementand disengagement of the connector block with the printed circuit board,the cover of the present invention advantageously enables the conductorwires to be readily clasped to the cover to provide strain relief forthe conductors. In this respect, openings 58 and 60 in legs 24 and 26 ofthe U-shaped wall are adapted to receive a flexible tying strap 75 whichextends beneath conductors 72 and the free ends of which are theninterconnected to draw the conductors into tightly clasped relationshipagainst bridging portion 28 of the cover. Tying strap 75 can be of anysuitable material for this purpose, such as, for example, paper orplastic coated wire, or a suitable string or cord material, Paper orplastic coated wire is preferred in that the ends thereof can be readilytwisted together and tightened to draw the conductor wires tightlyagainst the cover.

Preferably, openings 58 and 60 extend downwardly along legs 24 and 26 toprovide for the tying of various sizes of bundles of conductors in theforegoing manner. While a single elongated opening is provided in eachof the legs for this purpose, it will be appreciated that the legs couldeach be provided with a plurality of vertically spaced openings toachieve the same purpose. Further, it will be appreciated that suchopenings, whether single or multiple, could be provided at either orboth ends of the U-shaped wall or at other locations between theopposite ends thereof depending on the arrangement of the conductorwires leading from the connector block.

A modification of the cover described hereinabove is illustrated inFIGS. 5-9 of the drawing. The modified cover is produced from a blank ofplastic sheet material, such as polyethylene, corresponding structurallyto the blank illustrated in FIG. 1 with the exception of the openings 58and 60 provided in the latter blank, and the blank when erected forms acover structurally similar to the cover illustrated in FIGS. 2-4.Moveover, the modified cover is disclosed in assembled relationship witha connector block corresponding in structure to that illustrated inFIGS. 2-4. Accordingly, like numerals appear in FIGS. 5-9 to indicatecomponents of the cover corresponding to the components illustrated inthe embodiment of FIGS. 1-4.

Referring now to FIGS. 5-9, legs 24 and 26 and bridging portion 28 ofthe U-shaped wall define a space in which conductors 72 of connectorblock 62 are disposed when the cover is in assembled relationship withrespect to the connector block. Further, when the cover is erected andassembled on the connector block, tabs 34 and 46 overlie mounting lugs70 at the corresponding end of the connector block, and tabs 36 and 48facially engage the outer surfaces of tabs 30 and 42, respectively, torestrain lateral separation of legs 24 and 26.

In the present embodiment, leg 26 of the cover is provided with a tyingstrap 80 having an end 82 suitably interconnected at 83 with leg 26.Preferably, strap 80 is of plastic material, such as polyethylene, andend 82 of the strap can be attached to leg 26 such as by heat welding,or through the use of a separate fastener such as a metal or plasticrivet. Leg 26 is provided with an opening 84 beneath end 82 of thestrap, and leg 24 of the U-shaped wall is provided with an elongatedopening 86 opposite opening 84 and strap 80.

In the embodiment illustrated, the longitudinally opposite side edges ofopening 86 are provided with saw tooth-like serrations 88 and thelongitudinaly opposite side edges of strap 80 are provided with similarserrations 90. When the cover has been erected for assembly with aconnector block, strap 80 depends along the outer surface of leg 26 ofthe cover in the manner illustrated in FIGS. 7 and 9 of the drawing.When the cover is assembled with respect to the connector block and theconductor wires extending therefrom, the free end of strap 80 isinserted through opening 84 in leg 26 and thence through opening 86 inleg 24 in a manner whereby conductors 72 are disposed in the spacebetween bridging portion 28 and strap 80. The free end of the strap isthen pulled outwardly and upwardly of leg 24 so that the conductors aretightly clasped against bridging portion 28. The longitudinal widths ofstrap 80 and opening 86 are such that serrated edges 90 of the strapcooperatively interengage with serrated edges 88 of the opening to locktying strap 80 in place against unintended release of the claspedconductors. In the embodiment disclosed, such locking action is enhancedby providing the serrations 88 and 90 with generally parallellongitudinally extending top edges 88a and 90a, respectively.

While it is preferred that the opposite side edges of opening 86 andstrap 80 are serrated, it will be appreciated that other interengagingstructures between the strap and opening, including modifications of theserration structures illustrated, can be employed to achieve the samepurpose. Further, while serration of both edges of the strap and bothedges of the opening provides a more positive interengagement of thestrap and opening, interengagement can be achieved by serrations orother suitable interengaging edge structures along one or the other ofthe corresponding edges of the opening and strap. Futher, it will beappreciated that the interengagement can be accomplished by serratingthe opposite edges of the strap alone for engagement with straight sideedges of the opening. Many other arrangements for achieving a structuralinterengagement between the strap and opening will be apparent from orsuggested by the foregoing description and can be employed to achievethe desired clasping of the conductors.

While considerable emphasis has been placed herein on the fact that thetab arrangements at the opposite ends of the U-shaped wall of the coverare disposed adjacent the bottom or free edges of the legs of the U andextend longitudinally outwardly of the corresponding end edge of thecover wall, it will be appreciated that the tab arrangements can beprovided at other locations along the free edges of the legs of the U,and/or at other locations between the bridging portion and free edges ofthe legs of the U. Still further, it will be appreciated that the liketab components of the tab assemblies at opposite ends of the blank canbe disposed on the same side of the blank axis as opposed to beingdisposed in diagonally opposite comers of the blank as illustratedherein. Many modifications with regard to the location and structure ofthe components providing the tab assemblies can be made withoutdeparting from the purpose thereof.

Still further, while the material of the blank of the cover embodimentof FIGS. 2-4 is described as being sheet aluminum and the material ofthe blank of the embodiment of FIGS. 5-9 is described as beingpolyethylene, it will be appreciated that the metal can be other thanaluminum, the plastic other than polyethylene and that metal, plastic orother suitable sheet meaterial can be employed for both coverembodiments. Where metal is used for the cover of the embodiment ofFIGS. 5-9, the tying strap would be of plastic or other suitableflexible material. With regard to the tying straps of the coverembodiments described, the twisted end type strap for the embodiment ofFIGS. 2-4 can be replaced by other strap structures. For example, thestrap can be a plastic strip having an aperture at one end andcooperably serrated side edges extending therefrom so that the secondend of the strip can be inserted through the opening to form a loop. Thesize of the loop depends on the extent to which the second end is pulledthrough the opening, and the serrations and opening interengage toprevent unintended reverse movement of the second end through theopening. With regard to the strap for the embodiment of FIGS. 5-9, theattached strap can be replaced by a strap separable from the cover wall.For example, end 82 of the strap can be provided with a head structurewhich would engage leg 26 of the cover body around opening 84 and limitmovement of the strap through the opening when the serrated end of thestrap is inserted through openings 84 and 86 to underlie the conductors.

Since many embodiments of the present invention can be made and sincemany changes can be made in the embodiments herein illustrated anddescribed, it is to be distinctly understood that the foregoingdescriptive matter is to be interpreted merely as illustrative of thepresent invention and not as a limitation.

Having thus described our invention, we claim:

1. A cover for a multiple conductor electrical connector block,comprising generally U-shaped wall means of sheet material including apair of generally parallel legs and bridging means interconnecting saidlegs in spaced relationship, said legs having ends spaced from saidbridging means, and tab means on each of said legs interengaging saidlegs to limit spreading of said ends in the direction perpendicular tosaid legs, said tab means including a first tab on one of said legs anda second tab on the other of said legs, said first tab having an outersurface parallel to said one leg, a third tab extending from said secondtab toward said one leg, and a fourth tab extending from said third taband overlying said outer surface of said first tab to restrainseparation of said legs in said direction.

2. The cover according to claim 1, wherein said wall means includesopposed strap receiving openings, and strap means cooperable with saidopenings and wall means to clasp the conductors of a connector block inthe space between said wall means and strap means.

3. The cover according to claim 2, wherein said wall means has oppositeends, said opposed openings being located in said wall means adjacentone of said opposite ends.

4. The cover according to claim 2, wherein said strap means has oppositeends extending through said openings, means restraining one of saidopposite ends of said strap means against passage through thecorresponding opening in the direction toward the other opening, andmeans between said one end and the other of said opposite ends of saidstrap means for releaseably interengaging said strap means and saidother opening.

5. The cover according to claim 4, wherein said means for interengagingsaid strip means and said other opening includes serrations on saidstrap means interengageable with at least one of the edges defining saidother opening.

6. The cover according to claim 4, wherein said other opening hasopposed serrated edges and said strap means has opposed serrated edgesinterengageable therewith.

7. The cover according to claim 4, wherein said wall means has oppositeends, said tab means including tabs on each of said legs at each of saidopposite ends of said wall means.

8. A cover for a multiple conductor electrical connector block,comprising generally U-shaped wall means of sheet material including apair of generally parallel legs and bridging means interconnecting saidlegs in spaced relationship, said legs having ends spaced from saidbridging means, tab means on each of said legs interengaging said legsto limit spreading of said ends in the direction perpendicular to saidlegs, said wall means having opposite ends, said tab means includingtabs on each of said legs at each of said opposite ends of said wallmeans, said tabs including a first tab on one of said legs and a secondtab on the other of said legs, said first tab having an outer surfaceparallel to said one leg, a third tab extending from said second tabtoward said one leg, and a fourth tab extending from said third tab andoverlying said outer surface of said first tab to restrain separation ofsaid legs in said direction.

9. The cover according to claim 8, wherein said legs of said wall meanshave opposite end edges and said tabs are disposed longitudinallyoutwardly from the corresponding end edges of said legs.

10. The cover according to claim 9, wherein said legs, bridging meansand tabs are integral with one another.

II. The cover according to claim 10, wherein said third tab is aperturedfor interconnecting the cover with a connector block.

12. A cover for a multiple conductor electrical connector block,comprising generally U-shaped wall means of sheet material including apair of generally parallel legs and bridging means interconnecting saidlegs in spaced relationship, said legs having ends spaced from saidbridging means, tab means on each of said legs interengaging said legsto limit spreading of said ends in the direction perpendicular to saidlegs, said wall means including opposed strap openings, strap meanscooperable with said openings and wall means to clasp the conductors ofa connector block in the space between said wall means and strap means,said strap means having opposite ends extending through said openings,means restraining one of said opposite ends of said strip means againstpassage through the corresponding opening in the direction toward theother opening, means between said one end and the other of said oppositeends of said strip means for releasably interengaging said strip meansand said other opening, said wall means having opposite ends, said tabmeans including tabs on each of said legs at each of said opposite endsof said wall means, said tabs including a first tab on one of said legsand a second tab on the other of said legs, said first tab having anouter surface parallel to said one leg, a third tab extending from saidsecond tab toward said one leg, and a fourth tab extending from saidthird tab and overlying said outer surface of said first tab to restrainseparation of said legs in said direction.

13. The cover according to claim 12, wherein said legs of said wallmeans have opposite end edges and said tabs are disposed longitudinallyoutwardly from the corresponding end edges of said legs.

14. The cover according to claim 13, wherein said wall means is plasticand said strap means is a plastic strip, and means fastening said oneend of said strap means to said wall means to provide said restrainingmeans.

15. A sheet material blank for forming a U-shaped cover for anelectrical connector block, said blank having an axis, an exposed pairof side edges extending in the direction of said axis and opposed pairof end edges extending laterally with respect to said axis, first andsecond tabs extending from each of said end edges in the direction ofsaid axis and on opposite sides thereof, and tab means extending towardsaid axis only from said second tabs at each of said end edges, saidfirst tabs being located at one of the diagonally opposite corner areasof the blank, and said second tabs being located at the other of thediagonally opposite corner areas.

16. The blank according to claim 15, and openings through said blankbetween said end edges and on opposite sides of said axis.

17. The blank according to claim 15, wherein said sheet material ismetal.

18. A sheet material blank for forming a U-shaped cover for anelectrical connector block, said blank having an axis, an exposed pairof side edges extending in the direction of said axis and an opposedpair of end edges extending laterally with respect to said axis, firstand second tabs extending from each of said end edges in the directionof said axis and on opposite sides thereof, tab means extending towardaxis from one of said first and second tabs at each of said end edges,and openings through said blank between said end edges sheet material isplastic.

1. A cover for a multiple conductor electrical connector block,comprising generally U-shaped wall means of sheet material including apair of generally parallel legs and bridging means interconnecting saidlegs in spaced relationship, said legs having ends spaced from saidbridging means, and tab means on each of said legs interengaging saidlegs to limit spreading of said ends in the direction perpendicular tosaid legs, said tab means including a first tab on one of said legs anda second tab on the other of said legs, said first tab having an outersurface parallel to said one leg, a third tab extending from said secondtab toward said one leg, and a fourth tab extending from said third taband overlying said outer surface of said first tab to restrainseparation of said legs in said direction.
 2. The cover according toclaim 1, wherein said wall means includes opposed strap receivingopenings, and strap means cooperable with said openings and wall meansto clasp the conductors of a connector block in the space between saidwall means and strap means.
 3. The cover according to claim 2, whereinsaid wall means has opposite ends, said opposed openings being locatedin said wall means adjacent one of said opposite ends.
 4. The coveraccording to claim 2, wherein said strap means has opposite endsextending through said openings, means restraining one of said oppositeends of said strap means against passage through the correspondingopening in the direction toward the other opening, and means betweensaid one end and the other of said opposite ends of said strap means forreleaseably interengaging said strap means and said other opening. 5.The cover according to claim 4, wherein said means for interengagingsaid strip means and said other opening includes serrations on saidstrap means interengageable with at least one of the edges defining saidother opening.
 6. The cover according to claim 4, wherein said otheropening has opposed serrated edges and said strap means has opposedserrated edges interengageable therewith.
 7. The cover according toclaim 4, wherein said wall means has opposite ends, said tab meansincluding tabs on each of said legs at each of said opposite ends ofsaid wall means.
 8. A cover for a multiple conductor electricalconnector block, comprising generally U-shaped wall means of sheetmaterial including a pair of generally parallel legs and bridging meansinterconnecting said legs in spaced relationship, said legs having endsspaced from said bridging means, tab means on each of said legsinterengaging said legs to limit spreading of said ends in the directionperpendicular to said legs, said wall means having opposite ends, saidtab means including tabs on each of said legs at each of said oppositeends of said wall means, said tabs including a first tab on one of saidlegs and a second tab on the other of said legs, said first tab havingan outer surface parallel to said one leg, a third tab extending fromsaid second tab toward said one leg, and a fourth tab extending fromsaid third tab and overlying said outer surface of said first tab torestrain separation of said legs in said direction.
 9. The coveraccording to claim 8, wherein said legs of said wall means have oppositeend edges and said tabs are disposed longitudinally outwardly from thecorresponding end edges of said legs.
 10. The cover according to claim9, wherein said legs, bridging means and tabs are integral with oneanother.
 11. The cover according to claim 10, wherein said third tab isapertured for interconnecting the cover with a connector block.
 12. Acover for a multiple conductor electrical connector block, comprisinggenerally U-shaped wall means of sheet material including a pair ofgenerally parallel legs and bridging means interconnecting said legs inspaced relationship, said legs having ends spaced from said bridgingmeans, tab means on each of said legs interengaging said legs to limitspreading of said ends in the direction perpendicular to said legs, saidwall means including opposed strap openings, strap means cooperable withsaid openings and wall means to clasp the conductors of a connectorblock in the space between said wall means and strap means, said strapmeans having opposite ends extending through said openings, meansrestraining one of said opposite ends of said strip means againstpassage through the corresponding opening in the direction toward theother opening, means between said one end and the other of said oppositeends of said strip means for releasably interengaging said strip meansand said other opening, said wall means having opposite ends, said tabmeans including tabs on each of said legs at each of said opposite endsof said wall means, said tabs including a first tab on one of said legsand a second tab on the other of said legs, said first tab having anouter surface parallel to said one leg, a third tab extending from saidsecond tab toward said one leg, and a fourth tab extending from saidthird tab and overlying said outer surface of said first tab to restrainseparation of said legs in said direction.
 13. The cover according toclaim 12, wherein said legs of said wall means have opposite enD edgesand said tabs are disposed longitudinally outwardly from thecorresponding end edges of said legs.
 14. The cover according to claim13, wherein said wall means is plastic and said strap means is a plasticstrip, and means fastening said one end of said strap means to said wallmeans to provide said restraining means.
 15. A sheet material blank forforming a U-shaped cover for an electrical connector block, said blankhaving an axis, an exposed pair of side edges extending in the directionof said axis and opposed pair of end edges extending laterally withrespect to said axis, first and second tabs extending from each of saidend edges in the direction of said axis and on opposite sides thereof,and tab means extending toward said axis only from said second tabs ateach of said end edges, said first tabs being located at one of thediagonally opposite corner areas of the blank, and said second tabsbeing located at the other of the diagonally opposite corner areas. 16.The blank according to claim 15, and openings through said blank betweensaid end edges and on opposite sides of said axis.
 17. The blankaccording to claim 15, wherein said sheet material is metal.
 18. A sheetmaterial blank for forming a U-shaped cover for an electrical connectorblock, said blank having an axis, an exposed pair of side edgesextending in the direction of said axis and an opposed pair of end edgesextending laterally with respect to said axis, first and second tabsextending from each of said end edges in the direction of said axis andon opposite sides thereof, tab means extending toward axis from one ofsaid first and second tabs at each of said end edges, and openingsthrough said blank between said end edges and on opposite sides of saidaxis, at least a portion of the edges of one of said openings throughsaid blank being serrated.
 19. The blank according to claim 18, whereinsaid first tabs are located at one of the diagonally opposite cornerareas of the blank, said second tabs are located at the other of thediagonally opposite corner areas, and said tab means extend from saidsecond tabs.
 20. The blank according to claim 19, wherein said sheetmaterial is plastic.